I have a bathroom fan that needs to be vented through a hip roof. I am using rigid vent. I have the opportunity to pretty much go straight up to get through the roof, and it would be less than a 36" run.

Is it best to just go straight up?

Or should I run horizontally for a bit and then go straight up?

Thanks for any tips!

SeniorSitizen

10-05-2012 12:12 AM

Air exhausted from a bath can have relatively high dew point temperatures so if possible it's better if you can run it horizontal to the soffit with some down slope so the condensation in the pipe can drain to the outdoors in colder months.

federer

10-05-2012 01:26 AM

we ran ours straight up through roof but our run is only about 14inches

joecaption

10-05-2012 07:05 AM

For that short a distance as long as you insulate the pipe it will be fine.
I use PVC as the vent pipe so there's no rusting.

SeniorSitizen

10-05-2012 07:27 AM

In this application insulation is of little value without a heat source. We can look at the bath mirror condense at 75°F and have a good idea what a pipe in the attic at say 45° is going to do. Immediate water draining back unless the fan is way better than the ones I've seen.

JohnC20

10-05-2012 08:22 AM

Quote:

Originally Posted by Fairview
(Post 1024081)

Air exhausted from a bath can have relatively high dew point temperatures so if possible it's better if you can run it horizontal to the soffit with some down slope so the condensation in the pipe can drain to the outdoors in colder months.

This is interesting. I didn't think of this. I have the same issue as the op of this thread and is an upcoming project.